The headline on September 12 read: “Fatherhood Cuts Testosterone, Study Finds, for Good of the Family.” The article – on the front page of the NY Times – told of a recent study that found that becoming a father and engaging in childcare decreases a man’s testosterone levels.
For the scientists who produced the study, and for the newspaper’s science reporter alike, there is but a single, inevitable (and thus extra-cultural) consequence of this reported drop in testosterone levels: it makes men, on their view, less likely to seek multiple sex partners and more likely to be monogamous. The decrease in testosterone is thus “adaptive” to parenting, by virtue of it leading a man to be more anchored to a child’s mother—with the presumption (in the study and news report alike) being that the child in question is indeed the father’s genetic child (as well as the mother’s).
What these scientists and the NY Times's science journalist are entirely blind to is the possibility that there is no singular or automatic behavioral consequence of a drop in a man's testosterone level and, indeed, that a man’s response may depend a great deal on socialization and cultural values. Consider the possibility that some men in some contexts, if they experience a drop in “libido” (which is the presumed result of a drop in “testosterone,” in the study and NY Times alike), might seek to recapture or rekindle their “libido” by seeking out a new partner. In that case, if fatherhood indeed produces a drop in testosterone, the drop might lead to more sexual “infidelity,” rather than more “faithfulness”!
And what about the possibility that higher levels of testosterone are what make some men, at least in some social contexts, more monogamous—if sticking with an established partner provides a more reliable sex life than seeking out a new partner? Surely, it cannot be the universal experience, or essential character, of all men to be able to find a new sex partner, whenever they so desire--"at will," as it were. This is, though, precisely the presumption (the male fantasty, one might say) in a great many of the adaptationist fables told by evolutionary psychologists.
The larger question is this: how, given the range of human variability across time and space, can a group of scientists and science journalists be so stubbornly simple-minded (and so simple-mindedly stubborn) as to believe in a singular, determined, and universal behavioral outcome as a result of a drop in the level of a given hormone? And when will these scientists, and science journalists, finally get the more complex truth that there is always a complex interaction between human biology and culture?